Winter arrived hard and fast, bringing the issue of
heat to the
forefront. The in-slab
hydronic system is working fabulously on the main floor, but the hayloft is usually 5-10 degrees cooler and in need of supplemental heat. Since our future plans call for solar-thermal
hydronic heating, I want our system to be able to run at the lowest possible temperatures. That said, I opted for a '
hydronic wall' in the hayloft, instead of underfloor heating that requires somewhat higher fluid temps. To get started, I framed in a partition wall to divide the hayloft into two semi-private bedrooms (we decided not to extend the wall all the way up to keep the architecture of the high arched ceiling visible).
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Then I built a "
hydronic sandwich" using aluminum heat transfer plates between 'sleepers' of 3/4" foil-faced
isocyanurate insulation.
With Lisa's help, we routed 1/2"
pex tubing in a serpentine pattern through the wall, across the doorway framing, through the smaller side wall, then back to the starting point...then we repeated it in the second bedroom with a separate run of
pex...whew!
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Here is a closeup of the assembly:
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Finally, ready for drywall, which is screwed into the studs being
VERY CAREFUL not to puncture the tubing runs....
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The aluminum plates help conduct the heat out of the
pex tubing and into the drywall surface. The insulation 'sleepers' act as spacers between the drywall and studs, and help direct the heat out outward to the room. The drywall surface readily conducts the heat and radiates it outward to the room. By using this method rather than the more tradition underfloor
hydronic installation, more
BTUs can be delivered to the room at lower water temps...and it was a much easier and less expensive method in this case. The obvious downside to this method is the risk of puncturing the tubing with fasteners. I took
a lot of pictures of the assembly and documented the
pex locations so if we ever need to hang a picture on the wall, I'll know where not to pound a nail!